Dynamic structural characterization tests are known and applied in some industries for improving new designs of products and machines. For example, in the machine tool manufacturing industry, important machine tool parts such as main spindles may be subjected to dynamic structural characterization tests in which an exciting impact force may be applied to a main spindle being studied, and structural vibratory responses are measured and processed to obtain a response frequency spectrum. Information regarding the characterizations of the machine tools can then be obtained in an analysis of the response frequency spectrum of the main spindle and such information may be used in the design of a next generation of machine tools to improve the quality of the machine tools. Gas turbine engines are very complicated systems. Therefore, it is desirable but difficult to conduct an effective test for gas turbine engine dynamic characterization, particularly under engine operation conditions, in order to obtain information regarding dynamic characteristics of the engine system and particular engine structures which may be used for engine design improvement with respect to engine performance efficiency, safety issues, etc.
Accordingly, there is a need to provide a method and apparatus for running turbine engine dynamic characterizations.